An acoustic piano employs distinct and separate systems to transfer energy from a finger or actuator input force into an auditory, vibrational force. The transmission system, commonly called the action, is a network of levers, cushions and hammers that accepts finger/actuator input force through a collection of pivotal levers, known as keys. The keys and action focus this input force into rotating hammers of proportional density that are positioned to strike against tensioned wire strings. Both hammers and their corresponding strings are carefully constructed to match their acoustic properties, resulting in a tapered or graduated “scale” of components that cumulatively produce a multiple note span of musical frequencies. The strings act as media through which vibrational energy is transferred into an amplifier such as a soundboard, or electric speaker, where it ultimately is converted into audible sound.
Pianos can produce a wide range of volume. Large pianos can further expand this range to include very loud sounds, as heard in concert pianos that are expected to broadcast over an orchestra without the assistance of electric amplification. Pianos are prevalent in many cultures worldwide. They are present in many households, schools, institutions, etc. Inevitably, this proximity of volume producing instruments creates situations where sound control and reduction are necessary. Many piano manufacturers have provided muting mechanisms within their pianos to selectively restrict volume level. These mechanisms typically include a rotating rail that inserts an impact-absorbing material of varying density between the hammers and strings.